Noroviruses are the most common cause of acute viral gastroenteritis worldwide (Glass et al., N. Engl. J. Med. 361:1776-1785 (2009)). These viruses, which are members of the Caliciviridae family, are transmitted by a variety of routes and frequently cause outbreaks in closed settings such as schools, nursing homes, and cruise ships. Noroviruses can also be transmitted through contaminated foods and water, and they are the leading cause of foodborne disease in the U.S. (Scallan et al., Emerg. Infect. Dis. 17:16-22 (2011)) and perhaps worldwide (Patel et al., Emerg. Infect. Dis. 14:1224-1231 (2008); Ahmed et al., PLoS One 8:e75922 (2013)). Low infectious dose, high virus concentrations in the feces and vomitus of infected individuals, lengthy environmental persistence, and resistance to many commonly used sanitizers and disinfectants all contribute to the high degree of transmissibility of noroviruses (Hall et al., Emerg. Infect. Dis. 19:1198-1205 (2013)).
Despite their public health significance, routine detection of noroviruses in community settings or in food and environmental samples is limited. First, there is no cell culture model to propagate these viruses. Second, noroviruses have tremendous antigenic diversity. This antigenic diversity has complicated the development of broadly reactive antibodies, meaning that enzyme immunoassays have poor sensitivity (Costantini et al., J. Clin. Microbiol. 48:2770-2778 (2010); Kele et al., Diagn. Microbiol. Infect. Dis. 70:475-478 (2011)). Detection of noroviruses in food and environmental samples is even more complicated because virus concentrations are so low in these samples that it is necessary to perform labor-intensive and inefficient pre-concentration steps prior to detection (Knight et al., Crit. Rev. Microbiol. 39:295-309 (2013)).